تفاعل #1810811

معادلة التفاعل

sodium carbonate

Perchloric acid

(S)-pyroglutamic acid

tert-butyl acetate

→

ester

المردود 56.4%

(S)-tert-Butyl pyroglutamate

المردود 56.4%

المذيبات

ether

carbon tetrachloride

ظروف التفاعل

المعالجة

1. 1
   غسيلthe organic phase washed with saturated sodium hydrogen carbonate solution and brine
2. 2
   استخلاصThe aqueous phase was extracted with ethyl acetate
3. 3
   تجفيفdried (MgSO4)
4. 4
   ترشيحfiltered
5. 5
   أخرىthe solvent removed
6. 6
   أخرىto yield an oil to which
7. 7
   أخرىthe solvent evaporated in vacuo
8. 8
   أخرىto remove traces of acetic acid

الإجراء التجريبي

Perchloric acid (70% aqueous, 0.521 cm3, 6.05 mmol) was added dropwise to a stirred suspension of (S)-pyroglutamic acid 9 (1 g, 7.75 mmol) in tert-butyl acetate (12 cm3, 85.5 mmol). The mixture was stirred for 24 h then sodium carbonate (0.80 g, 7.60 mmol) was added cautiously, ether was added and the organic phase washed with saturated sodium hydrogen carbonate solution and brine. The aqueous phase was extracted with ethyl acetate, dried (MgSO4), filtered and the solvent removed to yield an oil to which was added carbon tetrachloride and the solvent evaporated in vacuo to remove traces of acetic acid to give ester 10 (0.81 g, 56%) as a white solid: δH (300 MHz; CDCl3; Me4Si) 1.48 [9H, s, C(CH3)], 2.33-2.45 (4H, m, 3-H2, 4-H2), 4.12-4.16 (1H, m, 5-H) and 6.16 (1H, br s, N—H); δC (75 MHz; CDCl3) 24.7 (CH2, 4-C), 27.8 [CH3, C(CH3)], 29.2 (CH2, 3-C), 55.9 (CH, 5-C), 82.3 [quat., C(CH3)], 170.9 (quat., 5-CO) and 177.7 (quat., 2-C).

المصدر